Comparison of cancer registry and clinical data as predictors for breast cancer survival

Background  In spite of the increasing amount of clinically relevant information for survival from breast cancer, the amount of data recorded in a population-based cancer registry is limited and the registry-based survival predictions are routinely made without clinical details. Objective  To find out how important is the role of screening and clinical tumor characteristics in addition to cancer registry information in describing the breast cancer survival. Methods  A representative clinical database on 483 breast cancer patients diagnosed during 1996–1997 in Tampere University Hospital Area was linked with Finnish Cancer Registry data and a survival model including the available registry variables was compared to models including screen-detection information and clinical tumor characteristics also. Results and conclusion  Estimates of registry stage and age act as surrogates for clinical variables and mammography-detection. The surrogacy was found to be almost complete indicating that clinical variables are not necessarily needed when making breast cancer mortality predictions based on a population-based cancer registry. In cases with dissimilar staging cancer registry stage gave a better picture of the breast cancer survival than the clinical stage. This work was performed in Finnish Cancer Registry, Helsinki, Finland.